The Sylyx
by Clare
Summary: Fifth Doctor era, set between "Castrovalva" and "Four To Doomsday". When the TARDIS is drawn off-course, the Doctor and his companions find themselves on a spacecraft whose entire crew has been wiped out. And the creature responsible is still on board.
1. The Sylyx: Part One

**The Sylyx: Part One**

The ancient spacecraft drifted through space, its crew long dead, drawing its energy from the stars to power it on its way. On the bridge, the desiccated corpses which were all that was left of the captain and his second-in-command were still slumped in their seats, a scenario repeated throughout the ship. The automatic life support system continued to function, but there was no living creature left on board to benefit from it. Except for the creature which lurked in the corridors . . .

The creature made a quick telepathic scan for signs of life - nothing. That wasn't surprising, however, as it had searched every inch of this craft and had claimed the life-force of everyone on board. There was no-one left and it knew that, in order to survive, it must soon leave. It must soon teleport out of here and find another spaceship to provide it with sustenance . . . Wait! It could sense something; another craft was nearby, though it could not tell what sort of craft it was, only that it was small enough to fit into one of the corridors. So there should be no need for the creature to teleport onto the craft it had just detected; all it had to do was teleport the craft in here. But was there anyone alive on board?

Pausing, the creature tried to detect life signs on board the smaller craft. It sensed four altogether, but its powers could not give it any more information, other than that two of the life-forms were male and two were female. Whoever they were, it would trap them and, then, it would do to them what it had done to the crew of this spacecraft. All it had to do was teleport their craft onto this ship which had been its larder . . .

* * *

A large blue box materialised in the corridor which led from the hold to the flight deck, a box which outwardly resembled a police box of the sort found on 20th Century Earth. Few who saw it would guess the secrets it contained. Few would guess it was really a machine capable of travelling in space and time. And few would guess that the interior was far more vast than its modest exterior suggested. Moments after the box had appeared, the doors opened and a fair-haired man with a stick of celery pinned to his beige coat stepped out, followed by three others: a young woman in her early twenties and two teenagers. The woman, dressed in a purple air hostess's uniform, was the first to speak. "Doctor," she said, glaring at the man with the celery on his coat, "you said you'd get me back to Heathrow. And this isn't Heathrow." She gestured round at their surroundings, obviously a corridor of some sort, though she could not tell where it was or where it might lead. And, quite frankly, she didn't want to know.

"Not to worry, Tegan," said the Doctor. "We've just been drawn off course." He pulled his sonic screwdriver, a small wand-like device, out of his pocket and held it in front of him, the device emitting a continuous high-pitched note as he activated it.

"Well, you can get right back on course," said Tegan, resisting the urge to call the Doctor every rude name she could think of. She did not want to be here; she was supposed to have started a job as a flight attendant and she didn't fancy having to tell her boss that she hadn't shown up for work because she had wandered into a spaceship disguised as a police box. "Look, you might enjoy gallivanting around, but some of us have got jobs to do."

"I'll get you on your flight," the Doctor told her, still taking readings. "Just as soon as I figure out where we are. Not to mention when," he added under his breath. At Tegan's request, he had tried to get her back to her own point in space and time, Earth in the year 1981, but the TARDIS did not always materialise where and when it was supposed to. The Doctor had gained a little more control than he had had at one point, when the TARDIS just seemed to materialise at random points in time and space, but it was still possible to program the machine for, say, the 20th Century and end up in the 10th, or in the 30th.

"This is a spaceship, isn't it?" The speaker was Nyssa, the other female in the small party of time-travellers, a young bio-physicist and the sole survivor of the Traken race. Unlike the more forthright Tegan, Nyssa had a much quieter nature, though she knew how to assert herself when she had to; she was also the most level-headed of the four. As the Doctor nodded in agreement, Nyssa added: "Do you know where it came from?"

"No," the Doctor replied. He had encountered many kinds of spacecraft on his travels, ranging from small scout craft to huge intergalactic transporters. This ship appeared to fit into the latter category, but he could not tell any more than that; its design was not something he had come across before. "But it would be interesting to find out," he went on, unable to resist the urge to go off and explore. This trait, this insatiable curiosity, had often put him at odds with his fellow Time Lords, most of whom were content simply to observe the Universe around them. But not the Doctor; he had "borrowed" an old Type 40 TARDIS and used it to go exploring space and time. "Come on!" he called to his companions, before marching off down the corridor.

"We'd better follow him," Nyssa said to Tegan.

Tegan had to agree; the Doctor was her only hope of getting back to her own time and, if anything happened to him . . . Before she could say anything, however, she suddenly realised something was wrong; one of their party was missing. "Wait!" she said. "Adric isn't here." She distinctly remembered that the young Alzarian had been with them when they left the TARDIS, so where was he now? And what were she and Nyssa supposed to do? Follow the Doctor or go looking for Adric and risk getting lost themselves?

"Keep calm," said Nyssa. "Adric must be here somewhere."

"But where?" Tegan demanded, though she could tell Nyssa didn't know the answer either. This was all she needed; not only had the Doctor materialised the TARDIS on an unknown spacecraft, instead of at Heathrow Airport like he was supposed to, Adric had disappeared. And that meant they would have to waste time looking for the boy, time the Doctor could have spent getting her home. Tegan sighed with exasperation as she realised what must have happened, that Adric must have wandered off to explore on his own. And she needed no-one to tell her that doing such a thing on an unknown spacecraft was, to say the least, foolish.

In the end, Nyssa decided they should follow the Doctor; at least they knew which direction he had gone, which was more than could be said for Adric. But there was always a chance that they might meet up with the boy along the way. Tegan, though she would much rather get out of here as quickly as possible, decided Nyssa's plan was probably the best course of action, the only alternatives being heading in a random direction or getting back into the TARDIS. The latter was out of the question anyway, since the Doctor had the key.

* * *

"Ah, Tegan and Nyssa," said the Doctor as his two female companions caught up with him. "I was wondering where you'd got to." He was examining something lying on the floor. Curious, Tegan hurried over to see for herself, only to recoil as she realised the thing the Doctor was examining was a human corpse - or humanoid, she reminded herself, recalling that, though the Doctor, Nyssa and Adric looked and sounded human, they were really members of three completely separate species. "Where's Adric?" the Doctor asked, straightening up from where he had been examining the body. "Isn't he with you? Well?" he pressed when neither Tegan nor Nyssa showed any signs of answering.

"That's what we came to tell you," Nyssa said, trying to avoid looking at the body, which was nothing more than a dried husk. She could not tell what had killed the person it had once been, but something told her that whatever had caused it was still on the ship, still looking for victims. "We think he went off somewhere by himself." There had, she recalled, been several side corridors branching off from the corridor where the TARDIS had materialised; Adric must have gone down one of them, but there was no telling which.

"Oh, that's all we need!" the Doctor said, rolling his eyes in response to Nyssa's news. "I've told him time and time again about wandering off." He sighed. "We'd better find him," he told Tegan and Nyssa, mentally preparing to give Adric the scolding of his life when he caught up with him.

Just then, a scream echoed through the corridors, causing the Doctor, Tegan and Nyssa to look at each other with a start. The cry was that of a young boy - and, as far as they knew, there was no-one on board the ship capable of making such a sound except Adric. It was obvious what had happened; while exploring on his own, Adric had run into trouble and, if the Doctor knew the young Alzarian, he had tried to deal with it by himself, only to find that he couldn't. Somehow, Adric's foolhardy courage would have to be reined in before people got hurt, including himself. With that in mind, the Doctor told Tegan and Nyssa to follow him and the three of them began to run in the direction of the scream.

As they ran, they saw more of the bodies, but no sign of anything alive. It was becoming increasingly obvious that something bad had happened on this abandoned spacecraft. Not only that, whatever had caused it was still on board - and, it seemed, Adric was its next target.

* * *

They caught up with Adric in one of the side corridors, finding him backed against a wall, being menaced by a creature like nothing Tegan and Nyssa had ever see before. It was at least seven feet tall, with mottled grey skin which resembled that of an elephant. There were no visible limbs except for a single tentacle, with which the creature was slowly reaching towards the terrified boy, ready to pull him towards itself. The Doctor had a fair idea what would happen next; in fact, he had little doubt that it had already happened several times on this craft. But he was not about to let it happen to Adric. Whipping out his sonic screwdriver, he sent a burst of high-pitched sound in the creature's direction, startling it and causing it to back off with its tentacle just inches from Adric.

"Adric!" he shouted to the boy, who still stood with his back against the wall. "Get out of here!" The creature could recover at any moment - the effect of the sonic screwdriver was not permanent - and the Doctor knew it was important to get clear before that happened. Not least because he had recognised the creature as one of the deadliest in the known Universe - a Sylyx, a creature which fed by draining the life-force from any living being it encountered. Sylyxes lived in interstellar space, rarely visiting planetary systems; instead, they lay in wait for passing spacecraft, teleported themselves on board and systematically wiped out every life-form they could detect. There was little doubt in the Doctor's mind that the Sylyx had been the thing which wiped out the crew of this spacecraft and it would have to be stopped before it could claim four more victims.

Somehow, Adric found the will to move and he hurried after the Doctor, Tegan and Nyssa as they ran back down the corridor which led to the TARDIS. The space-time machine was by far the safest place at the moment; when the doors were locked from the inside, the Sylyx would be unable to get at them - in theory. In practice, the Doctor had never encountered a Sylyx before and only knew about the creatures by repute; for all he knew, the Sylyx might somehow be able to break into the TARDIS. Either way, he would have to find some means of making sure it couldn't invade any more spacecraft.

But, as the four time-travellers reached the TARDIS and the Doctor unlocked the door, they were unaware that, in the side-corridor where they had encountered it, the Sylyx was beginning to stir . . .

* * *

As soon as everyone was safely inside the TARDIS and the doors were secured, the Doctor turned to Adric and gave the boy a look which let him know he was in serious trouble. "Adric," the Doctor said, not taking his eyes off the young Alzarian for a second, "what have I always told you about wandering off?"

Adric knew full well this was a rhetorical question, but the Doctor's tone of voice immediately put him on the defensive. "I just wanted to explore, that's all," he said, sounding like the petulant child the Doctor seemed determined to treat him as. He looked down at the floor, an action which reminded Tegan of an errant schoolboy about to receive a dressing-down from his headmaster.

"In that case, you should have waited for the rest of us and not gone off on your own," the Doctor told him. "Did you even think about how you were going to get back to the TARDIS?"

"Of course I did." Adric pulled something out of his pocket and held it in front of the Doctor's eyes. "Romana gave me this homing device - I could have found my way back easily." He remembered the day, on his home planet of Alzarius, when he had first met the Doctor and his then companions, a Time Lady named Romana and a robot dog called K-9. Romana had given him the homing device he was now brandishing before the Doctor to help him find his way back to the TARDIS when he went to warn his brother, Varsh, and his friends about Mistfall, a strange phenomenon which affected Alzarius every fifty years, but which Varsh had always insisted was a myth. Since then, however, Varsh had been killed, Romana and K-9 had left the TARDIS and the Doctor had regenerated, changing both his appearance and his personality. And, it seemed, this new Doctor had developed an annoying habit of treating Adric as though he was still just a child.

"But you didn't think about the dangers that might be waiting for you," the Doctor persisted, sensing that he was fighting a losing battle but determined to make his point. Then, as Adric opened his mouth to protest, he hurried on. "What you did was very foolish - you might have been badly hurt, even killed, if we hadn't found you. You may be a mathematical genius, but your common sense leaves a lot to be desired."

At this, Adric turned his back on the Doctor and muttered that he was "sorry" in a tone which sounded anything but apologetic. Tegan half-expected the Doctor to tell him to turn round and apologise properly, but, at that moment, Nyssa saved the boy from further scolding by asking the question which had been on the minds of all the Doctor's companions. "Doctor, what was that thing?"

"A Sylyx," replied the Doctor, who seemed to have forgotten that, moments before, he had been in the middle of giving Adric a severe reprimand. In answer to questions from his companions, he explained as much as he could about what a Sylyx was and how the creatures invaded passing spacecraft and drained the life-force of every living thing they encountered. "And you saw the results out there," he added, gesturing towards the TARDIS's doors.

"Doctor, there's one thing I don't understand," Tegan cut in, shuddering as she recalled the bodies she and the others had found. "How can that . . . thing live in space?" The idea was completely beyond her realms of experience; according to accepted scientific theory on Earth, a creature which lived in interstellar space should not exist. She was forgetting that the Doctor had far more experience in these matters than she did.

"Not all life needs a biosphere, Tegan," the Doctor replied, wondering for the umpteenth time why humans had such a narrow-minded view on what was and what wasn't scientifically possible. He knew there were living things out there in deep space, bizarre creatures that had evolved to exist in an environment which should have been totally devoid of life. Nevertheless, such creatures did exist and they did not only include the Sylyx. There was also the Wirrn, which the Doctor had encountered early in his previous incarnation; the "planet" Magla, which was really a gigantic amoeba with a crusty shell; a virus, found in the depths of Earth's solar system, which had had ideas way above its station . . . Just then, a sudden jolt sent all four members of the TARDIS crew tumbling to the floor.

* * *

Groaning, Tegan picked herself up, painfully aware that she had banged her hip in the fall. She glared at the Doctor, as though the jolt was somehow his fault - which it probably was. From what she'd seen of the TARDIS, it seemed the machine was one of the most unreliable pieces of junk she'd ever been a passenger on and, had the TARDIS not been her only hope of getting home, she might have been tempted to recommend a trip to a scrapyard. She did not know that the TARDIS had once spent several months parked in a scrapyard in 1960s London. In any case, she had no time to think about it before a shout from Adric distracted her.

"Doctor!"

The Doctor, Tegan and Nyssa turned in the direction the shout had come from. Adric was standing in front of the scanner screen, which showed a mass of mottled grey skin. The Sylyx was right outside the TARDIS - and it was trying to get in. It had been aware of the presence of the four time-travellers long before it encountered any of them and its instincts would not allow it to leave as long as there was potential prey in the vicinity. But this strange blue box was something it had never encountered before; it seemed to be a perfectly ordinary box, but there was something about it, something which was preventing the Sylyx from teleporting into it. The jolt the TARDIS crew had felt had been caused by the creature trying to break in.

"Doctor, get us out of here!" Tegan shouted, wanting to get as far from the Sylyx as possible. As far as she was concerned, the sooner she was back in her own time, the better. And it wasn't just because of the bodies she and the others had found, though that was part of it. It was all very well for Nyssa and Adric, she thought. Neither of them had any ties among their own people; in fact, Nyssa now had no people at all. But she had friends and family back in her own time, friends and family who must be growing increasingly worried about her, especially since her disappearance had coincided with the murder of her Aunt Vanessa. Not to mention that she was in danger of losing her job . . .

In response to Tegan's shout, the Doctor pressed the dematerialisation switch - to no avail. The TARDIS did begin to make the familiar thrumming sound it made when materialising or dematerialising, but it cut out almost immediately. The Doctor, muttering: "Come on, old girl!" under his breath, tried pressing the switch again, only to find that his second attempt to dematerialise was no more successful than the first. Tegan, Nyssa and Adric looked at him desperately, all three of them silently asking the same question. "It's no good!" the Doctor told them, giving the dematerialisation switch a third press, though he doubted it would do any good. "The controls aren't responding!"

"Another fault?" asked Adric, hurrying over to the console to see for himself. Of the four time-travellers, the Doctor was the only one who really understood the TARDIS, though Nyssa and Adric both understood some of the principles. As for Tegan, the fact that the one time she thought she was piloting the TARDIS, the machine had been on a pre-programmed course still rankled. It was another reminder that, for the time being, she was surrounded by intellectually superior aliens, one of whom seemed to enjoy belittling her.

"No, not this time," said the Doctor. He sighed as one of the switches came off in his hand. "Though it does need an overhaul," he added, imagining what Romana would say if she could see him now. Probably something about him falling behind with TARDIS maintenance. "No, it's something outside the TARDIS holding us back and . . ." He broke off as he realised Tegan was giving him what he had come to think of as _that_ look. "What?"

"Something outside the TARDIS?" Tegan demanded, keeping her voice as level as she could under the current circumstances. "Doctor, correct me if I'm wrong, but didn't we check all over that ship?"

Nyssa nodded to back her friend up. "We did. And the only life-forms on board are ourselves."

"And the Sylyx," the Doctor reminded his three companions. Then, it dawned on him. Before a Sylyx invaded a spacecraft, it must somehow take control of it, overriding the controls and making it impossible for those on board to escape. And, if the Sylyx could take control of the TARDIS, that meant it was even more dangerous than he had realised. The TARDIS contained many secrets which only a Time Lord was supposed to know and, if the Sylyx gained access to even a fraction of that data, there was no telling what it might do. It might even end up disrupting the very fabric of space and time, something the Doctor knew must never be allowed to happen; otherwise, the whole Universe would collapse into chaos. As it had nearly done during his recent encounter with the Master . . .

There was nothing else for it. Somehow, the Doctor and his companions would have to find a means of dealing with the Sylyx before it caused any more harm than it had already. It was too late to help the people on this ship, but at least the four time-travellers could do something about the thing which had killed them. The only question was, how could they neutralise the Sylyx without it claiming at least one more victim?

But the only alternative was staying here for all eternity, something none of the four wanted to do, especially Tegan.


	2. The Sylyx: Part Two

**The Sylyx: Part Two**

"Too bad K-9 isn't here," said Adric. He had only known K-9 for a short time, but it had been long enough for him to learn that there was very little that wasn't stored in the robotic dog's memory banks. That meant there was probably something about Sylyxes in there somewhere, ready to be accessed in response to a query from one of the TARDIS crew. There might even have been data on some inherent weakness in the creatures, one which the Doctor and his companions could use to their advantage.

"Well, he isn't," said the Doctor, resisting the urge to tell Adric to keep quiet if he had nothing useful to contribute. However, he had to admit that K-9 could have been invaluable in a situation like this, not only because of the data he contained, but because, as an inorganic entity, there were things he could do that beings of flesh and blood could not. But the Doctor quickly dismissed the thought; of the two versions of K-9 that had travelled with him, one was on Gallifrey with Leela and the other (the version Adric had known) was in E-Space with Romana. The Doctor had also built a third K-9, which he had left on Earth as a gift for his old friend, Sarah Jane. Which meant there would be no help from any version of the robot dog this time . . . "So we'll just have to figure this one out ourselves."

"What do you know about the Sylyx?" asked Nyssa, wondering how the Doctor planned to tackle the creature. She recalled the desiccated corpses she and the others had found while exploring the ship, all of them drained of their life-force and reduced to empty husks. And the same fate awaited herself, plus the Doctor, Tegan and Adric unless the Sylyx was stopped.

"Only what I've already told you." There was nothing else for it, the Doctor realised. He and his companions would have to go back out there and take their chances with the Sylyx if they were to have any hope of getting out of here. The TARDIS was immobilised by an outside influence and the Doctor knew from past experience that it would stay immobilised until the source of the problem was dealt with. The trouble was, where to begin . . .

* * *

Since the TARDIS controls were currently not working, the Doctor had to use an emergency handle to open the doors manually. It wasn't the first time he had had to do this, he recalled, remembering the time the TARDIS had been affected by the power drain caused by a sentient city on the planet Exxilon, but it was the first time he had done it since meeting any of his current companions. He cranked the doors open a crack and peered out, checking for any signs of the Sylyx; finding nothing, he opened the doors properly and told his companions to follow him.

"Great," Tegan said once the four of them were standing in the corridor once more. "What are we supposed to do now?" She was only here because the Doctor was her only hope of getting home; she would much rather have stayed in the TARDIS where the Sylyx couldn't get at her. But she dared not take the chance, dared not risk letting the man who was her "insurance policy" out of her sight.

"We split up," the Doctor replied. Then, before any of his companions could protest, he hurried on. "The Sylyx can't teleport in two directions at once. So, if we divide into pairs, there's a chance it won't know which pair to go for first - that should give us the time we need to find out how to deal with it." He clapped his hands together. "Right! Tegan, Nyssa, you two go that way," he said, pointing towards the rear of the ship. "Adric and I will head for the flight-deck and have a look round." Then, as a thought occurred to him, he pulled out his sonic screwdriver and handed it to Nyssa. "You might need this."

"But what about you and Adric?" Nyssa asked, looking down at the screwdriver in her hand.

"Well, I've only got one sonic screwdriver," the Doctor told her. "And I haven't got time to build a spare." Then, seeing that Nyssa still looked doubtful, he hurried on. "Look, you two go on - Adric and I will be all right." Nyssa, knowing from the expression on the Doctor's face that he meant what he said, did as she had been instructed and headed towards the rear of the ship. Tegan, however, stayed put, her arms folded and an expression which clearly said she did not think much of this plan etched on her face.

"Really?" she said. "And what happens if the Sylyx catches you? How am I supposed to get back to Heathrow then? Have you thought about that?" The thought of the desiccated corpses she and the others had found on this craft filled her with horror; she had always prided herself on being able to handle most things that came her way, but she was not equiped to deal with situations like this. Add to that the fact that the Doctor was prepared to risk his life (and Adric's, though she thought the young Alzarian could be a little overbearing at times) and she found herself longing to give him a piece of her mind. Not only that, the Doctor had promised to get her to the airport in time for her flight, a promise he would have considerable difficulty keeping if the Sylyx caught him.

"Look," the Doctor said, straining to keep a note of impatience from creeping into his voice, "I'll keep my promise. But I can't do anything while the Sylyx has the TARDIS immobilised. So the sooner you do as you're told, the sooner we'll get out of here."

Even Tegan knew not to push her luck too far and contented herself with muttering: "Men!" in an exasperated tone, before hurrying after Nyssa.

* * *

Once Tegan and Nyssa were out of sight, the Doctor turned his attention to Adric. "Right, follow me. And this time I mean follow," he added. With a Sylyx on the loose, the last thing he wanted was for Adric to go off on his own again. He had always made a point of warning his companions not to wander off, but it was a rule that seemed to get broken on a fairly regular basis. Perhaps the fright Adric had received during his earlier encounter with the Sylyx would be enough to deter him from taking any more detours, but the Doctor knew how reckless the boy could be.

For once, however, Adric did not seem to be in the mood to disobey orders and hurried after the Doctor as the latter headed in the direction of the flight deck. Neither of them had any idea what they were going to find there, though the Doctor hoped the onboard computer might still be working and that this could provide some clues as to this craft's planet of origin. Not that he had any real need to know, but finding out would give him something to do while he worked on a solution to a more pressing problem, namely getting rid of the Sylyx. Though he had never encountered one of the creatures before, he knew they were dangerous, that a Sylyx which infiltrated a spacecraft would not rest until it had wiped out every living thing on board, before moving on to its next target, and the next, and the next . . .

"Doctor," Adric said, as he and the Doctor hurried up the corridor which led to the flight-deck, "are Tegan and Nyssa going to be all right?"

"Oh, I should think so," the Doctor replied, shrugging. "Don't forget, they've got the sonic screwdriver."

"But they're female; that means they're not as rational as us."

"Now, don't make sweeping assumptions, Adric," the Doctor said, sensing that the boy was about to switch into "know-it-all" mode. He did not know if the kind of patronising attitude Adric's remark displayed was typical of Alzarian males, but Adric was not on Alzarius anymore, or even in E-Space. "We males don't have a monopoly on rational thinking." Besides, he added silently, there were times when irrational thinking and intuitive reasoning could be just as valuable. It was what distinguished living organisms from even the most sophisticated robots, such as the Movellans, who appeared to be organic at first glance but whose true nature was betrayed by their rigidly logical thought processes. Of course, they were currently the last thing on the Doctor's mind.

"And," the Doctor went on, "just because Tegan and Nyssa are female doesn't mean . . ."

But exactly what Tegan and Nyssa's gender didn't mean was destined to remain unspoken. At that moment, the Doctor and Adric found something blocking the corridor ahead, something big, something grey, something tentacled. The Sylyx - and it looked like it meant business. The Doctor, remembering his previous encounter with the creature, instinctively reached into his pocket for his sonic screwdriver, only to come up empty-handed. "Oh, of course!" he said with a touch of frustration. "I gave it to Nyssa." Which, he reflected, meant it was just his luck that he and Adric should be the ones the Sylyx chose to target.

The Doctor knew he and Adric had three options. Try to get past the Sylyx, easier said than done when neither of them had the sonic screwdriver (or any other noise-making device) with him; make a run for it and try to meet up with Tegan and Nyssa, though the Sylyx could easily get ahead of them thanks to its ability to teleport; return to the TARDIS, which was currently immobilised. Whichever course of action he and Adric took presented problems, but the only alternative was to stay put and let the Sylyx catch them.

* * *

"Don't you think we should be heading back to the TARDIS?"

Tegan had asked this several times already, but Nyssa had been engrossed in doing something with the sonic screwdriver (which she was currently holding like a tracking device) and had not replied. This time, however, she did. "And what good would that do? Until we find a way to deal with the Sylyx, the TARDIS isn't going anywhere - and neither are we." She said this in her usual matter-of-fact tone, but Tegan was not in the mood to listen to reason.

"Well, it's better than what we're doing now," she shot back. "Which is wandering around a spaceship with a monster on the loose! And suppose that . . . thing's got the Doctor and Adric!" As annoying as she had often found Adric in the short time she had known him, Tegan realised she did not wish anything bad would happen to the boy - and ending up desiccated like the Sylyx's previous victims ranked pretty high in her list of bad things. And she still needed the Doctor to get her back to Heathrow, where the most she would have to worry about was male passengers who couldn't keep their hands to themselves. "You can stay if you want, but I'm going back to the TARDIS," she added. Then, before Nyssa could stop her, she stormed off in the direction the two of them had just come.

Nyssa had never met someone as headstrong as Tegan before, someone who would do whatever it took to get her own way. It was obvious to the young Traken that Tegan would not be happy until she was back in her own time and, since the Doctor had failed to get her home, she was prepared to take matters into her own hands. But surely even Tegan wouldn't attempt to move the TARDIS herself, not when she knew the Sylyx still had it immobilised. Besides, they still didn't know how to deal with the Sylyx, what its weaknesses were or anything like that. Nyssa sighed as she realised she had no choice but to go after Tegan and try to make her see sense.

* * *

The Doctor and Adric stood back-to-back, watching the Sylyx to see what it was going to do next. The creature was studying the two male humanoids, almost as if it was trying to decide which of them it should go for first. Indeed, it was studying them, but not for the reason the Doctor and Adric feared; rather it was studying them to find out what species they were. Sylyxes do not "see" in the sense that a humanoid would understand the word, but they can detect the basic bodyform and approximate age of any living organism. This Sylyx could sense one life-form that was not quite fully adult and another that was centuries old but had the body of someone considerably younger.

And it knew by some deep instinct that it was the older of the pair who was the key to the strange box it had tried to infiltrate earlier. And, in the same instant, it realised where the older male came from - and _what_ he was. A Time Lord, one of the most powerful races in existence and a serious threat; few races could match the Time Lords when it came to mental powers. Fortunately, most Time Lords were content simply to observe and never interfered in the affairs of others, but the Sylyx could sense that this one was different, that he was concerned for the three young people who had arrived with him. And the Sylyx was going to use that concern to its advantage.

Before the Doctor could stop it, it extended its tentacle and pressed it against Adric's forehead. The Doctor looked on in horror, expecting to see Adric turn into a desiccated shell, but the boy simply stayed where he was, though his brown eyes did become strangely unfocused. And, when he spoke, it was in a voice very unlike his own, a voice which sounded powerful but also menacing, the sort of voice which would terrify almost anyone who heard it.

_"You are the Doctor."_

The Doctor did not reply; he knew it was not Adric speaking, that the Sylyx was simply using the Alzarian as a living puppet. He had seen this kind of thing before: a creature, incapable of verbal speech itself, taking control of another living being in order to communicate. The Doctor did not have to question how the Sylyx knew who he was; it must have read Adric's mind and absorbed everything the boy knew about him. Then, it had started projecting its voice through Adric in order to communicate.

Still using Adric as a puppet, the Sylyx continued in the same menacing tone. _"You will reveal to me the secret of your time-travel machine, the TARDIS, so that I may use it to travel anywhere in time and space. With your help, Doctor, the Sylyx race will have mastery over all."_

But the Doctor had heard similar statements before, from members of various races. And he was no more impressed this time than he had been on previous occasions; megalomaniacs were all the same in his opinion, not caring what happened to anyone else so long as they got the power they craved. "It won't be as easy as you think," he told the Sylyx, with more bravado than he felt. "The TARDIS needs very careful handling."

_"In that case, I'll give you an ultimatum. Reveal the secret - or I'll teleport out of this ship and take the boy with me!"_

"No!" The Doctor knew what would happen to Adric if he entered the vacuum of space without a space helmet; he had already seen it happen to Katarina and countless others. The Sylyx could survive in outer space for long periods, but a humanoid would perish almost instantly. On the other hand, there was no way he was going to reveal any of the TARDIS's secrets to a creature like the Sylyx; there was no telling how much damage it would do if it gained access to all of time and space. His one slim hope of avoiding the dilemma was that the Sylyx was bluffing. "If you do that, you won't learn anything!" he shouted, his voice rising in pitch as it often did under stress.

_"But are you willing to take the chance? The boy looks on you as a father figure - would you betray his trust?"_

The Doctor knew the Sylyx was manipulating him, playing on his heroic instincts. Even if he told the creature what it wanted to know, there would be nothing to stop it from desiccating himself and Adric anyway; they would be of no further use to it. After that, the Sylyx would go after Tegan and Nyssa, then, armed with the knowledge it had forced from the Doctor, begin a rampage through time and space. A Sylyx was dangerous at the best of times, but one that knew even a fraction of the Time Lords' secrets . . .

* * *

In the end, the Doctor was saved from having to make a decision which could spell disaster for the whole of creation. Nyssa appeared around the corner with Tegan close behind her; having found the TARDIS still immobilised, the two friends had decided the best course of action was to find the Doctor and Adric. Or rather Tegan had insisted on it. The Doctor's first instinct was to tell them to get away, but then he remembered how the Sylyx had backed off when he gave it a taste of his sonic screwdriver earlier.

"Nyssa!" he shouted. "Use the screwdriver!" It was only a temporary solution, but it should stun the Sylyx long enough for the four of them to get away.

Nyssa pulled the sonic screwdriver out of her pocket and held it at arm's length as she activated it, sending a pulse of high-pitched sound in the Sylyx's direction. As it had before, the Sylyx backed off immediately and stopped attacking. In the process, it lost its hold on Adric, who stood looking as though he had no memory of the last few minutes but otherwise seemed unhurt. Even so, the Doctor wasn't about to take chances and hurried to the boy's side. "Adric, are you all right?" he asked.

Adric blinked, confused; the last thing he remembered was that he and the Doctor had been heading for the flight deck when they found the Sylyx blocking their path. Everything that had happened to him in the minutes since was lost to him; he had no idea what the Doctor was talking about, nor how Tegan and Nyssa came to be here. He opened his mouth to ask, but the Doctor stalled Adric's question with one of his own. "Quick, tell me. What is a prime number?"

Adric felt somewhat insulted that the Doctor had asked what was, to the young Alzarian, a very basic maths question, but he answered nevertheless. "A number only wholly divisible by itself and one. I learned that when I was six years old," he added for no reason other than to remind everyone present that he was a mathematical genius. And, just in case it wasn't already obvious enough, he pointed to the badge for mathematical excellence pinned to his shirt.

"Good, no harm done," said the Doctor, before Tegan could butt in and tell Adric to stop being such a know-it-all. He looked at the still-stunned Sylyx, then at his three companions, before making a decision. "Right, change of plan. We're all going back to the TARDIS." But, just as he was about to head in that direction, he noticed Tegan looked at him in a way which said she thought this was the most ridiculous plan in the Universe.

"And what good will that do?" With that thing . . ." She nodded towards the Sylyx. " . . . around, that crate of yours isn't going anywhere."

The Doctor bristled slightly at hearing his TARDIS described as a "crate", but he quickly regained his composure. "Perhaps not," he told her. "However, it does contain some items that might be useful for dealing with our friendly neighbourhood Sylyx." And, without further explanation, he shepherded his three companions together and led them towards the TARDIS.

* * *

As soon as everyone was back on board the TARDIS, the Doctor began to outline his plan, a plan which had occurred to him after he had twice seen the Sylyx's reaction to the sonic screwdriver. "But the screwdriver alone won't be enough," he explained. "Even if I crank it up to its highest setting. So . . ." He strolled over to Nyssa and Adric, who were standing next to the console, and rested his hands on their shoulders. "So we're going to build a sonic amplifier. Or, rather, Nyssa and I are. Adric, I'll need you to do a few calculations."

"Great," said Tegan, rolling her eyes as she realised she was being left out of the Doctor's plan. True, from what she could tell, it involved a load of scientific mumbo jumbo she couldn't begin to understand, but she hated just standing around doing nothing. "And what am I supposed to do?" Of course, what she wanted to do was get back to her own time, but that clearly wasn't an option at the moment.

"Just trust us," was all the Doctor said, before he, Nyssa and Adric left the Console Room and headed for the laboratory.

"Whatever you say, Doc," Tegan muttered, seconds after Adric had closed the door behind him. She looked at the console and sighed; if it wasn't for the Sylyx draining the TARDIS's energy, she could have a crack at getting out of here. After all, how hard could it be to pilot a TARDIS? All you had to do was press a switch and the machine would take you to wherever you wanted to go. Or not, as the case may be . . .

Recalling that it was the Doctor's incompetence that had landed everyone in this mess in the first place, Tegan mentally reeled off the long tirade to which she would subject the Time Lord when she next saw him. She had given him a specific place and time and she had expected to be delivered to that place and time. Apart from anything else, she had a job to do, not that the Doctor seemed to realise that.

* * *

Eventually, after what felt like an interminable wait, the door to the Console Room opened and the Doctor appeared, carrying the most bizarre-looking device Tegan had ever seen and followed by Nyssa and Adric, both of whom were carrying two sets of headphones. Tegan was not sure what she had been expecting, but she had a feeling it wasn't the strange device the Doctor was carrying. The sonic amplifier (there was nothing else the device could be) seemed to be based around an old dansette record player that had had various accoutrements, most of which Tegan could not begin to name, added to it. The young Australian woman fixed the Doctor with a look which said she thought he was completely mad.

The Doctor ignored Tegan's look. "Right," he said, addressing all three of his companions, "let's go and take care of that Sylyx." But, even as he spoke, doubts began to creep into his mind; he didn't even know if this plan would work. If it didn't, the Sylyx was sure to find a way to make him reveal the secrets it had tried to force from him earlier. And that could not only lead to it claiming four more victims, but also to it gaining access to secrets only a Time Lord was supposed to know. No, he must not think like that. So he quickly dismissed any thoughts of potential failure and ushered his companions out of the TARDIS.

As soon as they were all out in the corridor, the Doctor turned to his companions and began to outline his plan. His theory was that the Sylyx, which had no use for a sense of hearing in the vacuum of space, was sensitive to sonic vibrations, as suggested by the way it reacted to the sonic screwdriver. "So, if we can produce a note of the right pitch and sustain it for long enough," he explained, "it should take care of the Sylyx for good."

"You mean kill it?" asked Nyssa, who found the idea of destroying any living thing troubling.

The Doctor nodded grimly. "I don't like it any more than you," he told her. "But I can't let a creature like that learn any Time Lord secrets. It would threaten the whole created Universe - that's why we've got to stop it." Without saying another word, he set off down the corridor, as his companions followed him.

As they walked, a troubling thought occurred to Tegan. "Doctor," she said, "how exactly are we going to find the Sylyx? It could be anywhere in this ship."

"No need to worry about that, Tegan," the Doctor replied, speaking a little too airily for Tegan's liking.

"And why not?" Tegan said, biting back the diatribe she longed to unleash on the Doctor. The four of them were risking their lives here - and the Doctor was acting as though this was a Sunday school outing. Clearly, she thought, the fall from the radio telescope at the Pharos Project had done more than cause the Doctor's appearance to change, not that she had had much chance to get to know his previous incarnation; it had also unhinged him. And this was the man she was counting on to get her home.

"Because," the Doctor replied, "we don't have to find it. It will find us."


	3. The Sylyx: Part Three

**The Sylyx: Part Three**

The Doctor's words did not inspire confidence in Tegan; being found by the Sylyx was exactly what she was worried about. Not for the first time, she bitterly regretted the curiosity which had caused her to venture into the TARDIS. Ever since then, it seemed she had been in trouble non-stop. She had hoped that, once the Master was dealt with, she would be able to go back to her own time and get on with her life. But it seemed things were not going to be as straightforward as she had hoped.

Having no other choice in the matter, other than to go back to the currently immobilised TARDIS, she sighed and continued down the corridor. Along the way, she passed more desiccated corpses (or were they the same corpses she had encountered earlier?) but saw no sign of the thing which had killed them. However, she knew the Sylyx was on board this ship somewhere, just waiting to attack. Was the Doctor really serious about being able to stop it with what looked to her like a souped-up record player?.

Drawing level with Nyssa, Tegan took hold of the Traken's arm, slowing her to a standstill. "Is the Doctor mad?" she whispered, trying to avoid being overheard by the madman in question. She did not know that the Doctor's senses were much sharper than hers - and those were just the five senses shared by all four members of the TARDIS crew. "That thing out there could kill us all!"

Nyssa was the sort of person who could generally be counted on to keep a cool head in a crisis, in contrast with the more volatile Tegan. Indeed, despite the differences in temperament between the two females, they had quickly become such close friends that they were almost like sisters. Nyssa realised she would miss Tegan once the latter was back on Earth. Right now, however, it looked as though Tegan was on the verge of panic and Nyssa knew instinctively what she must do. Neither the Doctor nor Adric would be much use in this situation; the Doctor was currently preoccupied with his plan for dealing with the Sylyx and Adric had a habit of rubbing Tegan the wrong way, so anything the boy said might only make matters worse.

"Just trust him," Nyssa said, nodding towards the Doctor. "He knows what he's doing."

"Like he knew what he was doing when he landed us here instead of at Heathrow?" Tegan asked, still annoyed with the Doctor for failing to comply with her request. Especially when she had not asked to become a member of the TARDIS crew in the first place.

"That wasn't the Doctor's fault. He said something had drawn the TARDIS off course."

"The Sylyx?" Tegan's voice had the same edge it had had when she asked the Doctor about her Aunt Vanessa's fate.

Nyssa nodded slowly. "There's nothing else it could have been. Anyway, you can't blame the Doctor every time something goes wrong."

Tegan saw that there was logic in Nyssa's statement, but that did not lessen her annoyance. She sighed. "I guess not," she said. "It's just that he promised to get me home and . . ." She broke off as she noticed the tears welling up in her friend's eyes. "I'm sorry," she added. "I was forgetting your home isn't there any more." She recalled how upset she had been when she learned that her aunt had been killed, murdered by the Master. That had been bad enough, but the Master had also caused the destruction of the entire Traken race apart from Nyssa, as well as of Traken itself. Tegan could not begin to imagine what it must be like to know that the place you had grown up in was gone forever.

"I'm all right," Nyssa said, regaining her composure. "But we'd better catch up with the Doctor and Adric."

* * *

The Sylyx could sense that the Doctor and his companions were near - very near. And it could also sense that all four of them were moving in the same direction, with the two males in the lead. Good, that meant it wouldn't have to expend energy teleporting all over the ship in order to hunt them down. It had not fed since it cornered the last few surviving members of the ship's original crew and teleportation inevitably used up the energy it had absorbed. And then there was the Doctor; if it could force him to reveal even a fraction of the Time Lords' secrets, it would have the whole of space and time at its disposal. And that meant it could go anywhere and anywhen to get the energy it needed. It did not see its actions as evil; as far as it was concerned, it was simply doing what it needed to do in order to survive.

But, if it wanted to feed on the four time-travellers, it first had to catch them and that meant teleporting ahead of them. Teleportation used up energy, but it didn't have much choice. Sylyxes are not built for moving under their own physical power, having no need to do so in their natural habitat of interstellar space; instead, they have evolved the ability to teleport themselves. So it summoned up the energy it needed to transport itself into the corridor ahead of the Doctor and his companions.

And, moments later, the Doctor and his companions came round the corner.

* * *

"Oh, rabbits!" muttered Tegan as soon as she saw the mound of grey flesh that was the Sylyx. Her instinct was to run, but something told her that, if she tried that, she wouldn't get far. Instead, she gazed round at the others, noting their reactions. Nyssa had stepped back a pace when she saw the Sylyx, though Adric was too proud to show fear whether he felt it or not. But hopefully the memory of his earlier encounters with the creature would keep him from trying anything foolish. Knowing Adric, though, that couldn't be guaranteed.

As for the Doctor, he quickly hid the sonic amplifier he and Nyssa had built behind his back and stepped forward, flashing the Sylyx a disarming smile. Tegan was about to run forward and demand to know what he thought he was doing, but the Doctor spoke first. "Ah, good to see you. Maybe we can come to some kind of agreement." He made it sound as though he was willing to negotiate, but he had learned long ago that some races were not open to negotiation. And, from what he'd gathered, Sylyxes ranked alongside Daleks, Cybermen and other races that were impossible to reason with. At best, they might agree to your terms if it suited their purposes, but as soon as you were of no further use to them, you became just as disposable as you had been before you attempted negotiations.

The Sylyx ignored him.

"Look, if you're still after my TARDIS, I've already given my answer," the Doctor said, still keeping the sonic amplifier hidden behind his back. "And it hasn't changed. So . . ." He broke off as a dark-haired, yellow-shirted figure suddenly broke ranks and ran towards the Sylyx. "Adric! Get back!" Already he could see the Sylyx's tentacle reaching towards the boy.

Adric, who had in a moment of impulsive courage, attempted to tackle the Sylyx directly, looked round at the sound of the Doctor's voice. This was just the opening the Sylyx needed. Before the Doctor could stop it, it wrapped its tentacle around the Alzarian's arm and began to drag him towards itself. This time, it was not going to use Adric as a living puppet; it was preparing to absorb his life force and turn him into another desiccated shell.

Adric struggled to break free, but the Sylyx's grip was too strong. His mind was filled with memories of Varsh, who must have been just as afraid when the Marshmen attacked him, dragging him to his doom as Adric tried in vain to save him. The sight of the boy fighting to break free from the creature that had killed so many caused something to snap in Tegan. As irritating as Adric could be, she could not let him end up like the crew of this spacecraft, no matter how much his attacker disgusted her. She ran forward and grabbed hold of Adric's other arm, attempting to pull him away.

"You disgusting . . . thing!" she shouted at the Sylyx. "Let that boy go!"

But the Sylyx's only response was to tighten its grip on Adric. It was not going to be denied so easily; as soon as it was through with the young Alzarian, Tegan would be the next on the menu. And, unless the Doctor revealed the secrets that were known only to Time Lords, the Sylyx would then go after Nyssa. It could sense that the Doctor cared about all three of his companions and it was going to exploit that concern to its own ends. Adric's attempt to tackle it physically, thereby bringing himself within range of its tentacles, was an unexpected bonus.

* * *

The Doctor looked on in horror as he realised both the oldest and the youngest of his three companions were in danger, both because of Adric's recklessness. Had the boy learned nothing from his earlier encounters with the Sylyx? Surely even someone as lacking in common sense as him could see that attempting to tackle the creature directly would only get you killed. Not only that, but Tegan had risked her own life in an attempt to save him. There was nothing else for it, the Doctor realised; he would have to use the sonic amplifier.

He pulled the device out from behind his back and switched it on. It immediately began to emit a high-pitched humming noise, one which the Doctor and his companions could tolerate provided it didn't continue for too long, but which the Sylyx would find painful. Sure enough, as it had done when the sonic screwdriver was used against it, the Sylyx left off attacking as soon as it felt the vibrations from the amplifier. As the tentacle it had wrapped around Adric's arm went limp, the boy stumbled away, dragging Tegan with him. But, though his two friends were safe for the moment, the Doctor was not through yet; the Sylyx needed to be dealt with.

"Quick!" he shouted, preparing to crank up the volume. "Get your headphones on!"

"You mean these?" Tegan asked, picking up one of the pairs of headphones which Adric had dropped when he attempted to tackle the Sylyx.

"Yes, unless you want your eardrums to burst." The Doctor had used sound as a weapon before, such as the time he had used an amplified recording of Victoria's screams to get rid of the Weed Creature which had invaded a gas rig. And experience had taught him that it was generally a good idea to have some form of auditory protection when fighting an enemy with sound. There was only so much the humanoid ear could stand; even he, a Time Lord, would not be able to endure the noise of the sonic amplifier at full volume for long. Sooner or later, he would have to put himself into a state of total sensory withdrawal and he could not afford to be out of action right now.

Tegan could tell the Doctor was serious, so she put the headphones on and adjusted them to fit as the Doctor retrieved the second set of dropped headphones and placed them over his ears. Glancing at Nyssa and Adric, Tegan saw that both of them were already wearing headphones; no doubt the Doctor had warned them in advance that his plan would involve making a great deal of noise. Well, they had helped to build the sonic amplifier.

Satisfied that everyone's ears were adequately protected, the Doctor slowly turned the volume control on the amplifier up to maximum. The high-pitched noise the device had been making since it was first switched on rapidly grew into a deafening screech.

* * *

Or at least it would have been deafening had anyone been able to hear it. The Doctor's headphones were not just ordinary headphones; they completely cut out all external sound, effectively rendering their wearer deaf. Tegan found the sensation rather bizarre, like watching television with the sound turned down as low as it would go, though, had she come from just a few years in her own future, she might have compared it to pressing the Mute button on a remote control. You knew the sounds had not gone away, but you couldn't hear them. It was a strange, isolating experience.

But Tegan was not tempted to remove her headphones, even for a second; she knew doing so while the sonic amplifier was operating at full volume risked damaging her hearing permanently. And she wouldn't be much use as an air stewardess if she couldn't hear instructions from the cabin crew. Of course, that would be a moot point unless the Doctor could get her back to Heathrow and, if his next attempt was as successful as this one had been . . . In any case, presented with a choice between temporary and possibly permanent deafness, she decided she prefered the former.

The Sylyx, meanwhile, was beginning to suffer as a direct result of the sonic onslaught it was being subjected to. Since there is no sound in space, Sylyxes have no sense of hearing, but they are sensitive to vibrations especially those at the higher end of the scale. And the noise emitted by the sonic amplifier was piercing every cell in its body, disrupting every molecule, causing it to . . . Sensing what was about to happen to it, the Sylyx attempted to teleport away, only to find that the disruption to its body was so great that it could no longer use its powers.

The Doctor realised what was going to happen a few seconds before it actually happened. With the sonic amplifier still running, he shouted a warning to his companions, a warning none of them could hear thanks to the headphones they were using to protect their ears from the effects of the amplifier. Consequently, the entire TARDIS crew was caught directly in the firing line as the Sylyx's body began to shake and . . .

. . . exploded, covering everyone in green gunge. Tegan uttered several words not used in polite conversation as bits of Sylyx landed in her hair and on her stewardess's uniform. It was going to take forever to get her clothes clean, assuming the TARDIS even had a laundry. She had never thought to ask, having expected to be going home before she could get mixed up in another of the Doctor's bizarre adventures. But things hadn't worked out the way she had hoped and, as a result, she was now covered in Sylyx gunge. Her only consolation was that the Doctor, Nyssa and Adric were in just as much of a mess.

* * *

The Doctor switched off the sonic amplifier, then waited for the noise from the device to die down before removing his headphones. Satisfied that there was no longer any danger of anyone's eardrums being perforated, he flashed a thumbs-up signal to his companions to let them know they could remove their headphones. Once they had done so, the four of them stood looking at each other for several seconds before Adric broke the silence.

"It worked."

The Doctor looked at the spot where the Sylyx had stood moments before. "I knew it would in theory, but practice is another matter." He turned to his companions. "And now we'd better get back to the TARDIS and clean ourselves up," he added, apparently noticing for the first time the mess everyone was in. And it wasn't just himself and his companions; bits of the Sylyx were spread all over the corridor, not that it mattered now. With the danger removed, this craft (whose planet of origin he still didn't know) could be left to drift on through space.

"Doctor," Tegan asked, as she and the others began to make their way back towards the TARDIS, "what happened?"

The Doctor's reply was a long-winded explanation about the effects extreme sonic vibrations could have at a molecular level, especially for a creature that, rather than having a sense of hearing, was adapted to detect the vibrations made by auditory waves. "Or, to put it another way," he added, "this device made more noise than the Sylyx's body could stand, causing it to explode. Rather like glass will break if you expose it to intense vibrations." In fact, that was why he had asked Adric to help with the sonic amplifier; he had needed someone to calculate the precise pitch at which the device would need to operate for maximum effect.

"In any case," the Doctor went on. "The Sylyx is gone and that means we should be able to move the TARDIS again."

"Doctor," Tegan said, a slight edge creeping into her voice, "make sure you move it to Heathrow this time."

"Well, I'll do my best," the Doctor replied. "But, as this experience may have told you, I can't always guarantee that we will end up where we want to go."

"You mean you can't even control your own TARDIS?"

"I can - to an extent. But it's an old model and that means it's not always reliable."

Tegan made no reply to this. Old and unreliable or not, the TARDIS was her only hope of getting back to her own time, so she resisted the urge to throw every insult she knew at the Doctor and followed him, Nyssa and Adric back to the corridor where the space-time machine had first materialised.

* * *

"Doctor," Nyssa asked, "what's going to happen to that spaceship?"

The Doctor and his companions were grouped around the TARDIS console, travelling through the Time Vortex. All four of them had cleaned themselves up so that no trace of the Sylyx remained on any of them; Tegan had berated the Doctor at length for getting everyone in such a mess in the first place. In reply, the Doctor had told her it was that or allow the Sylyx to gain access to the secrets it had wanted to know, secrets which could threaten the fabric of the Universe if they got into the wrong hands - or tentacles. Now, with the Sylyx neutralised, the TARDIS was on the move once more, though whether it would materialise at Heathrow as Tegan hoped was another matter.

"Nothing," the Doctor said in reply to Nyssa's question. "Apart from drifting through space for all eternity. Kind of like the _Mary Celeste_," he added, recalling the time the TARDIS had briefly materialised on the famous sailing ship. However, he, Ian, Barbara and Vicki had left before the Daleks, who were pursuing the TARDIS through time and space, arrived in one of their own time machines and frightened the _Mary Celeste's_ crew into abandoning ship.

"What's the _Mary Celeste_?" asked Adric, whose knowledge of Earth - and of N-Space in general - still contained several gaps. Many of the things which Tegan took for granted, such as lighthouses and railway stations, had not existed on Alzarius and therefore meant nothing to him.

The Doctor glanced up at the sound of the Alzarian's voice, then quickly turned back to the console. "A ship from Earth's history - you can look it up in the library." Right now, he was concentrating on trying to get Tegan back to Heathrow and did not have time for long explanations.

And, with that, the TARDIS continued its journey through the Time Vortex.


End file.
